Biophysical Settings

The Biophysical Settings (BPS) layer represents the vegetation that may have been dominant on the landscape prior to Euro-American settlement and is based on both the current biophysical environment and an approximation of the historical disturbance regime.

Map units are based on NatureServe's Ecological Systems classification and represent the natural plant communities that may have been present during the reference period. Each BPS map unit is matched with a model of vegetation succession, and both serve as key inputs to the LANDSUM landscape succession model. As used in LANDFIRE (LF), map unit names represent the natural plant communities that may have been present during the reference period.

LF uses BPS to depict reference conditions of vegetation across landscapes. The actual time period for this data set is a composite of both the historical context provided by the fire regime and vegetation dynamics models and the more recent field and geospatial data used to create it.

Attribute tables for LANDFIRE grid data, served in CSV (comma separated values) file format, are available on the Data Distribution Site and landfire.gov. Generally, these attribute tables provide information pertaining to the grid class value along with class descriptions or labels for these values. Attribute tables, such as the Existing Vegetation Type, provide additional attribute fields that can provide crosswalk links to other classification themes. Color mapping fields are also provided within the attribute tables, providing a standardized, consistent LANDFIRE color mapping schema for these data layers. The attribute files are in comma separated value (csv) format that can be easily converted to other formats to meet user needs.

The attribute tables are provided as a convenience as calculations with grid data will automatically drop attributes. For example, if a grid is clipped, the rowid, value, and count are the only attributes retained. Attribute fields can be reattached to the grid using a join attribute function having the "value" attribute as the link.